Eudora is an 85-year-old woman living alone in her childhood home in Southeast London. Weary of her long life and the emotional weight of her family history, she seeks to maintain a strictly solitary existence. She secretly applies to an assisted-suicide clinic in Switzerland to take control of her final days, though her plans face disruption from well-meaning new neighbors. She favors dark, practical clothing and routinely pushes people away to avoid further emotional pain.

Rose is a lively 10-year-old girl who recently moved to London with her family seeking a fresh start after school difficulties. She dresses in clashing, bright outfits composed of sequins and neon colors. She possesses an exceptionally cheerful disposition and easily breaks through social barriers, frequently inviting herself over for tea or organizing outings for her older neighbors.

Stanley is an elderly neighborhood resident who recently lost his beloved wife, Ada. He masks his deep grief with constant joking and a familiar, overly friendly manner. Despite his own loneliness and depression, he makes a concerted effort to check on others in the community and forms a close bond with both Eudora and the young girl next door.

Albert is Eudora's father. He leaves his family behind in London to fight in World War II. He serves as the primary source of warmth in young Eudora's life and entrusts her with the heavy responsibility of looking after her pregnant mother while he is deployed.

Beatrice is Eudora's mother. She struggles deeply with the realities of wartime London and single motherhood. She often relies heavily on Eudora to manage the household and finds it difficult to cope with the chaotic energy of her younger child, leading to a fractured family dynamic.

Stella is Eudora's younger sister, born into a stressful wartime environment. She grows up as a chaotic, headstrong child who constantly clashes with their mother. Her difficult behavior creates friction in the household and requires Eudora to forfeit her own happiness to manage the fallout.

Maggie is Rose's mother and Eudora's new neighbor. Currently pregnant, she is seeking a fresh start for her family in London. She proves to be open-hearted and willing to share her own vulnerabilities, forming an unexpected connection with Eudora over shared grief.

Eddie is a young man Eudora dates during her youth. He becomes intertwined in the complex dynamics of the Honeysett family, eventually serving as a major source of conflict and tragedy involving both sisters.

Sam is Eudora's childhood crush. He remains a recurring figure in her life over several decades, offering her brief glimpses of potential romantic connection that conflict with her family duties.

Dr. Liebermann is a physician at the Klinik Lebenswahl. She carefully assesses Eudora's mental state over the phone, insisting that patients must embrace their current lives and ensure their choices are not merely the result of treatable loneliness.

Petra handles the administration and check-in calls for the Klinik Lebenswahl. She monitors Eudora's social activities, keeping careful notes on whether Eudora is forming community ties that might affect her eligibility for assisted suicide.

Jada is a classmate who quickly attaches herself to Rose. She exhibits poor manners and frequently makes snide remarks, attempting to isolate Rose from other potential friends by discouraging her enthusiasm.

Elsie is an elderly woman Eudora meets during a medical emergency. She shares Eudora's dread of dying in a clinical setting and provides the crucial brochure for the Swiss clinic that sets Eudora's plans in motion.

Sylvia is Eudora's best friend during her youth. The two share activities like shopping and double dates, representing the conventional social life Eudora attempts to build before her family obligations overwhelm her.

Rob is Rose's father and Maggie's husband. He is highly protective of his daughter and deeply invested in helping her build a better social life after she experienced bullying at her previous school.